It is common practice in the medical field to include a radiopaque element in surgical sponges so that such sponges can be detected by x-ray if inadvertently left in the body cavity following a surgical procedure. In this context, surgical sponges include folded gauze and nonwoven fabric swabs, woven and knitted laparotomy pads, and cotton balls.
A common x-ray detectable material used in conjunction with surgical sponges is a polymeric filament or ribbon loaded with an x-ray opaque filler material such as barium sulfate. Suitable polymeric materials include polyisobutylene, polyvinyl chloride and copolymers of vinyl acetate and vinyl chloride.
The x-ray detectable elements have been attached to the base sponge material by a variety of techniques. In the case of gauze swabs, a filament has been interwoven into the fabric of the gauze, or attached to the surface of the fabric and folded into the sponge construction. In the case of laparotomy sponges, an x-ray detectable ribbon has been enclosed in a seam stitched along one edge of the pad, and an x-ray detectable filament has been incorporated into the woven handle strap of the pad.
Securing an x-ray detectable element to a nonwoven sponge has presented a problem since nonwovens are produced continuously and at high speed and sewing or stitching the x-ray detectable filament to the nonwoven is not practical from a manufacturing point of view. Some success was had in attaching the x-ray detectable filament to the surface of the nonwoven, usually by heat fusing or resin bonding. Although the X-ray detectable element could be secured by these methods, the security of attachment was not sufficient to prevent the x-ray detectable element from being pulled off the fabric under some conditions of use.
Commonly assigned application U.S. Ser. No. 605,369 discloses a nonwoven surgical sponge with an x-ray detectable element as an integral part of the fabric construction. The x-ray detectable element, a yarn or monofilament, is entangled into the interior of a layer of entangled fibers, and, in the case of the monofilament, hot calendered to secure it within the fabric. In the process disclosed therein the x-ray detectable element is placed between two fibrous webs prior to entangling. The webs may comprise a percentage of fusible fibers.
It is an object of the present invention to provide a x-ray detectable nonwoven surgical sponge with a simple construction and method of manufacture. These and other objects of the present invention will be apparent from the ensuing description and claims.